Southern San Juan

Avalanche

Matt Huber Chris Bilbrey · Dec 11, 2020 · Southern San Juan

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Weather

7 inches of new snow fell during our trip bringing storm totals to over a foot. Southwest winds near treeline were strong enough to blow and drift new snow onto leeward(northeast) slopes.

Snowpack

Sensitivity increased dramatically as storm totals inched closer to a foot or in wind exposed areas where the new snow was slightly stiffer. Near treeline on northeast-facing slopes, extended column tests produced propagating results on isolation at the new snow interface. Shooting cracks up to 15 feet in front of our skis were observed.

Avalanche

A small natural was observed on a wind-exposed east-facing terrain feature near treeline. Trimming cornice above Alberta's Cousin produced a very soft storm slab that propagated across the entire path, about 250 meters across failing on the buried facets below the new snow.